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1.
Conserv Biol ; 30(4): 827-35, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-26808168

RESUMEN

Conflicts between local people's livelihoods and conservation have led to many unsuccessful conservation efforts and have stimulated debates on policies that might simultaneously promote sustainable management of protected areas and improve the living conditions of local people. Many government-sponsored payments-for-ecosystem-services (PES) schemes have been implemented around the world. However, few empirical assessments of their effectiveness have been conducted, and even fewer assessments have directly measured their effects on ecosystem services. We conducted an empirical and spatially explicit assessment of the conservation effectiveness of one of the world's largest PES programs through the use of a long-term empirical data set, a satellite-based habitat model, and spatial autoregressive analyses on direct measures of change in an ecosystem service (i.e., the provision of wildlife species habitat). Giant panda (Ailuropoda melanoleuca) habitat improved in Wolong Nature Reserve of China after the implementation of the Natural Forest Conservation Program. The improvement was more pronounced in areas monitored by local residents than those monitored by the local government, but only when a higher payment was provided. Our results suggest that the effectiveness of a PES program depends on who receives the payment and on whether the payment provides sufficient incentives. As engagement of local residents has not been incorporated in many conservation strategies elsewhere in China or around the world, our results also suggest that using an incentive-based strategy as a complement to command-and-control, community- and norm-based strategies may help achieve greater conservation effectiveness and provide a potential solution for the park versus people conflict.


Asunto(s)
Conservación de los Recursos Naturales/economía , Ecosistema , Ursidae , Animales , Animales Salvajes , China , Financiación Personal , Humanos , Motivación
2.
Proc Natl Acad Sci U S A ; 110(27): 10916-21, 2013 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-23776222

RESUMEN

For decades, scholars have been trying to determine whether small or large groups are more likely to cooperate for collective action and successfully manage common-pool resources. Using data gathered from the Wolong Nature Reserve since 1995, we examined the effects of group size (i.e., number of households monitoring a single forest parcel) on both collective action (forest monitoring) and resource outcomes (changes in forest cover) while controlling for potential confounding factors. Our results demonstrate that group size has nonlinear effects on both collective action and resource outcomes, with intermediate group size contributing the most monitoring effort and leading to the biggest forest cover gain. We also show how opposing effects of group size directly and indirectly affect collective action and resource outcomes, leading to the overall nonlinear relationship. Our findings suggest why previous studies have observed differing and even contradictory group-size effects, and thus help guide further research and governance of the commons. The findings also suggest that it should be possible to improve collective action and resource outcomes by altering factors that lead to the nonlinear group-size effect, including punishing free riding, enhancing overall and within-group enforcement, improving social capital across groups and among group members, and allowing self-selection during the group formation process so members with good social relationships can form groups autonomously.


Asunto(s)
Conservación de los Recursos Naturales/métodos , Animales , Biodiversidad , China , Conservación de los Recursos Naturales/estadística & datos numéricos , Ecosistema , Procesos de Grupo , Humanos , Dinámicas no Lineales , Apoyo Social , Árboles , Ursidae
3.
J Environ Manage ; 127: 86-95, 2013 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-23685121

RESUMEN

Systematic evaluation of the environmental and socioeconomic effects of Payments for Ecosystem Services (PES) programs is crucial for guiding policy design and implementation. We evaluated the performance of the Natural Forest Conservation Program (NFCP), a national PES program of China, in the Wolong Nature Reserve for giant pandas. The environmental effects of the NFCP were evaluated through a historical trend (1965-2001) analysis of forest cover to estimate a counter-factual (i.e., without-PES) forest cover baseline for 2007. The socioeconomic effects of the NFCP were evaluated using data collected through household interviews carried out before and after NFCP implementation in 2001. Our results suggest that the NFCP was not only significantly associated with increases in forest cover, but also had both positive (e.g., labor reduction for fuelwood collection) and negative (e.g., economic losses due to crop raiding by wildlife) effects on local households. Results from this study emphasize the importance of integrating local conditions and understanding underlying mechanisms to enhance the performance of PES programs. Our findings are useful for the design and implementation of successful conservation policies not only in our study area but also in similar places around the world.


Asunto(s)
Conservación de los Recursos Naturales/métodos , Ecosistema , Motivación , China , Factores Socioeconómicos , Árboles/crecimiento & desarrollo
4.
Land use policy ; 33: 42-53, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26146431

RESUMEN

After long periods of deforestation, forest transition has occurred globally, but the causes of forest transition in different countries are highly variable. Conservation policies may play important roles in facilitating forest transition around the world, including China. To restore forests and protect the remaining natural forests, the Chinese government initiated two nationwide conservation policies in the late 1990s -- the Natural Forest Conservation Program (NFCP) and the Grain-To-Green Program (GTGP). While some studies have discussed the environmental and socioeconomic effects of each of these policies independently and others have attributed forest recovery to both policies without rigorous and quantitative analysis, it is necessary to rigorously quantify the outcomes of these two conservation policies simultaneously because the two policies have been implemented at the same time. To fill the knowledge gap, this study quantitatively evaluated the effects of the two conservation policies on forest cover change between 2001 and 2008 in 108 townships located in two important giant panda habitat regions -- the Qinling Mountains region in Shaanxi Province and the Sichuan Giant Panda Sanctuary in Sichuan Province. Forest cover change was evaluated using a land-cover product (MCD12Q1) derived from the Moderate Resolution Imaging Spectroradiometer (MODIS). This product proved to be highly accurate in the study region (overall accuracy was ca. 87%, using 425 ground truth points collected in the field), thus suitable for the forest change analysis performed. Results showed that within the timeframe evaluated, most townships in both regions exhibited either increases or no changes in forest cover. After accounting for a variety of socioeconomic and biophysical attributes, an Ordinary Least Square (OLS) regression model suggests that the two policies had statistically significant positive effects on forest cover change after seven years of implementation, while population density, percent agricultural population, road density, and initial forest cover (i.e. in 2001) had significant negative effects. The methods and results from this study will be useful for continuing the implementation of these conservation policies, for the development of future giant panda habitat conservation projects, and for achieving forest sustainability in China and elsewhere.

5.
Ambio ; 52(1): 95-106, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35997989

RESUMEN

As the world grows more interconnected through the flows of people, goods, and information, many challenges are becoming more difficult to address since human needs are increasingly being met through global supply chains. Global shocks (e.g., war, economic recession, pandemic) can severely disrupt these interconnections and generate cascading consequences across local to global scales. To comprehensively evaluate these consequences, it is crucial to use integrated frameworks that consider multiple interconnections and flows among coupled human and natural systems. Here we use the framework of metacoupling (human-nature interactions within as well as across adjacent and distant systems) to illustrate the effects of major global shocks on the evolution of global interconnectedness between the early 1900s and the 2010s. Based on these results we make a few actionable recommendations to reduce the negative impacts of an ongoing global shock, the COVID-19 pandemic, to promote global sustainability.


Asunto(s)
Internacionalidad , Humanos , COVID-19/epidemiología , Recesión Económica
6.
Sci Rep ; 13(1): 11254, 2023 07 12.
Artículo en Inglés | MEDLINE | ID: mdl-37438427

RESUMEN

Over the last few years, understanding of the effects of increasingly interconnected global flows of agricultural commodities on coupled human and natural systems has significantly improved. However, many important factors in environmental change that are influenced by these commodity flows are still not well understood. Here, we present an empirical spatial modelling approach to assess how changes in forest cover are influenced by trade destination. Using data for soybean-producing municipalities in the state of Mato Grosso, Brazil, between 2004 and 2017, we evaluated the relationships between forest cover change and the annual soybean trade destination. Results show that although most of the soybean produced in Mato Grosso during the study period (60%) was destined for international markets, municipalities with greater and more consistent soybean production not destined for international markets during the study period were more strongly associated with deforestation. In these municipalities, soybean production was also significantly correlated with cattle and pasture expansion. These results have important implications for the sustainable management of natural resources in the face of an increasingly interconnected world, while also helping to identify the most suitable locations for implementing policies to reduce deforestation risks.


Asunto(s)
Conservación de los Recursos Naturales , Glycine max , Humanos , Animales , Bovinos , Agricultura , Brasil , Bosques
7.
Ambio ; 52(6): 1040-1055, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36976464

RESUMEN

Numerous narrow marine passages around the world serve as essential gateways for the transportation of goods, the movement of people, and the migration of fish and wildlife. These global gateways facilitate human-nature interactions across distant regions. The socioeconomic and environmental interactions among distant coupled human and natural systems affect the sustainability of global gateways in complex ways. However, the assessment and analysis of global gateways are scattered and fragmented. To fill this knowledge gap, we frame global gateways as telecoupled human and natural systems using an emerging global gateway, the Bering Strait, as a demonstration. We examine how three telecoupling processes (tourism, vessel traffic, and natural resource development) impact and are impacted by the coupled human and natural system of the Bering Strait Region. Given that global gateways share many similarities, our analysis of the Bering Strait Region provides a foundation for the assessment of other telecoupled global gateways.


Asunto(s)
Comercio , Transportes , Océanos y Mares
8.
Sci Total Environ ; 904: 166681, 2023 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-37673258

RESUMEN

Climate change mitigation and biodiversity conservation are two major environmental actions that need to be effectively performed this century, alongside ensuring food supply for a growing global human population. These three issues are highly interlinked through land management systems. Thus, major global food production regions located in biodiversity hotpots and with potential for carbon sequestration face trade-offs between these valuable land-based ecosystem services. The state of Mato Grosso in Brazil is one such region, where private lands that have been illegally used for agriculture could be restored to natural vegetation - with potential benefits for climate change mitigation and biodiversity conservation, although with potentially negative effects on food production. To address this challenge, in this study we used a multicriteria nexus modeling approach that considers carbon stocks, priority areas for biodiversity conservation, and the opportunity for food production, to develop scenarios of land allocation that aim to balance the benefits and drawbacks of ecosystem restoration. Results show that forcing landowners to restore their individual lands compromises the potential for a "green land market" throughout the Amazon biome in which private landowners with lower food production capacities (e.g., less connected to markets and infrastructure) would benefit from restoration programs that compensate them for the inclusion of environmental restoration among their economic activities, instead of taking large economic risks to produce more food. We additionally highlight that strategic ecosystem restoration can achieve higher gains in biodiversity and carbon with lower costs of restoration actions and with minimal impacts on agriculture. Analyses like ours demonstrate how scenarios of land allocation that simultaneously address climate mitigation and biodiversity conservation through ecosystem restoration, while also minimizing possible impacts on food production, can be sought to move the world towards a sustainable future.


Asunto(s)
Cambio Climático , Ecosistema , Humanos , Brasil , Conservación de los Recursos Naturales/métodos , Biodiversidad , Agricultura/métodos , Carbono
9.
Ecol Modell ; 229: 16-24, 2012 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-22389548

RESUMEN

Conservation investments are increasingly being implemented through payments for ecosystem services (PES) for the protection and restoration of ecosystem services around the world. Previous studies suggested that social norms have substantial impacts on environmental behaviors of humans, including enrollment of PES programs. However, it is still not well understood how social norms are affected by the design of PES programs and how the evolution of social norms may affect the efficiency of conservation investments. In this paper, we developed an agent-based simulation model to demonstrate the evolution and impacts of social norms on the enrollment of agricultural land in a PES program. We applied the model to land plots that have been enrolled in China's Grain-to-Green Program (GTGP) to examine reenrollment in an alternative payment program when the current payments ceased. The study was conducted in Wolong Nature Reserve where several thousand plant and animal species, including giant pandas, may benefit from the reenrollment. We found that over 15% more GTGP land can be reenrolled at the same payment if social norms were leveraged by allowing more than ten rounds of interactions among landholders regarding their reenrollment decisions. With only three rounds of interactions, an additional 7.5% GTGP land was reenrolled at the same payment due to the effects of social norms. In addition, the effects of social norms were largest at intermediate payments and were smaller at much higher or much smaller payments. Even in circumstances where frequent interactions among landholders about their enrollment decisions are not feasible, policy arrangements that divide households into multiple waves for sequential enrollment can enroll over 11% more land at a given payment level. The approach presented in this paper can be used to improve the efficiency of existing PES programs and many other conservation investments worldwide.

10.
Ambio ; 40(3): 274-84, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21644456

RESUMEN

Conservation policies are increasing in response to human-induced ecosystem degradation, but little is known about their interplay with natural disasters. Through an analysis of satellite imagery and field data we evaluated the impacts of a devastating earthquake on forest recovery and avoided forest loss estimated to have been obtained by two of the largest conservation programs in the world. Results show that more than 10% of the forests in Wenchuan County, Sichuan province, China were immediately affected by the 2008 earthquake, offsetting some gains in forest cover observed since the enactment of the conservation programs. But without the enactment of these conservation programs, the combined effects of human disturbance and earthquake-induced landslides could have severely reduced the region's forest cover. The continuation--and enhancement--of incentives for participation in conservation programs will be important for reducing the environmental impacts of the combined effects of human disturbance and natural hazards not only in the study area but also in many disaster-prone regions around the world.


Asunto(s)
Conservación de los Recursos Naturales , Terremotos , Política Ambiental , China , Árboles
11.
Sci Rep ; 11(1): 18662, 2021 09 20.
Artículo en Inglés | MEDLINE | ID: mdl-34545181

RESUMEN

Human-environment interactions within and across borders are now more influential than ever, posing unprecedented sustainability challenges. The framework of metacoupling (interactions within and across adjacent and distant coupled human-environment systems) provides a useful tool to evaluate them at diverse temporal and spatial scales. While most metacoupling studies have so far addressed the impacts of distant interactions (telecouplings), few have addressed the complementary and interdependent effects of the interactions within coupled systems (intracouplings) and between adjacent systems (pericouplings). Using the production and trade of a major commodity (soybean) as a demonstration, this paper empirically evaluates the complex effects on deforestation and economic growth across a globally important soybean producing region (Mato Grosso in Brazil). Although this region is influenced by a strong telecoupling process (i.e., soybean trade with national and international markets), intracouplings pose significant effects on deforestation and economic growth within focal municipalities. Furthermore, it generates pericoupling effects (e.g., deforestation) on adjacent municipalities, which precede economic benefits on adjacent systems, and may occur during and after the soybean production takes place. These results show that while economic benefits of the production of agricultural commodities for global markets tend to be localized, their environmental costs tend to be spatially widespread. As deforestation also occurred in adjacent areas beyond focal areas with economic development, this study has significant implications for sustainability in an increasingly metacoupled world.

12.
Sci Total Environ ; 777: 145995, 2021 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-33676225

RESUMEN

Globally, the number and extent of terrestrial protected areas (PAs) are expanding rapidly. Nonetheless, their impacts on preventing forest loss and the factors influencing the impacts are not well understood, despite the critical roles of forests in biodiversity conservation, provision of ecosystem services, and achievement of the United Nations' Sustainable Development Goals. To address this important knowledge gap, we quantified the impacts of 54,792 PAs worldwide on preventing forest loss from 2000 to 2015, and assessed important landscape and management factors affecting the impacts of PAs. Although the majority (71.4%) of the PAs contributed to preventing forest loss, only 30.5% of forest loss in the PAs have been prevented. PAs with higher rates of forest loss in their surrounding regions, located at lower elevations, within a few hours of travel from the nearest city, with higher agricultural productivity, and permission for fewer human uses were better able to prevent forest loss. Impacts on preventing forest loss were similar regardless of whether the PAs were privately or publicly owned. Our findings highlight the potential benefits of strict protections, involving private entities in the establishment of PAs, and situating PAs in areas exposed to high risks of forest loss to enhance the capacity to combat global forest loss.

13.
Conserv Biol ; 24(6): 1469-78, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20586786

RESUMEN

Ecosystem services are being protected and restored worldwide through payments for ecosystem services in which participants are paid to alter their land-management approaches to benefit the environment. The efficiency of such investments depends on the design of the payment scheme. Land features have been used to measure the environmental benefits of and amount of payment for land enrollment in payment for ecosystem services schemes. Household characteristics of program participants, however, may also be important in the targeting of land for enrollment. We used the characteristics of households participating in China's Grain-to-Green program, and features of enrolled land to examine the targeting of land enrollment in that program in Wolong Nature Reserve. We compared levels of environmental benefits that can be obtained through cost-effective targeting of land enrollment for different types of benefits under different payment schemes. The efficiency of investments in a discriminative payment scheme (payments differ according to opportunity costs, i.e., landholders' costs of forgoing alternative uses of land) was substantially higher than in a flat payment scheme (same price paid to all participants). Both optimal targeting and suboptimal targeting of land enrollment for environmental benefits achieved substantially more environmental benefits than random selection of land for enrollment. Our results suggest that cost-effective targeting of land through the use of discriminative conservation payments can substantially improve the efficiency of investments in the Grain-to-Green program and other payment for ecosystem services programs.


Asunto(s)
Conservación de los Recursos Naturales/métodos , Ecosistema , Eficiencia Organizacional , China , Conservación de los Recursos Naturales/economía , Análisis Costo-Beneficio
14.
J Plant Physiol ; 254: 153277, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32979788

RESUMEN

The absorption of Photosynthetically Active Radiation (PAR) by different foliar pigments defines the amount of energy available for photosynthesis and also the need for photoprotection. Both characteristics reveal essential information about productivity, development, and stress acclimation of plants. Here we present an approach for the estimation of the efficiency by three foliar pigment groups (chlorophylls, carotenoids, and anthocyanins) at capturing light, via the absorption coefficient derived from leaf reflectance spectra. The absorption coefficient (and hence light capture efficiency) of the pigment is quantitatively related to the ratio of light absorbed by each pigment group over the total amount of light absorbed by the leaf. The proposed approach allows discerning the contribution of pigment groups to the overall light absorption, despite the strong interference by other pigments with overlapping absorption spectra. For photosynthetic pigments, like chlorophylls, this is indicative of the energy captured for photosynthesis and hence of potential plant productivity. For photoprotective pigments, like anthocyanins or secondary carotenoids, it gives information about the spectral ranges where their optical screening works best and their screening capacity. In addition, the approach allows the selection of optimal spectral bands where different pigments operate. Such information improves our understanding of the phenological, physiological and photosynthetic dynamics of plants over space and through time, useful for developing better monitoring and management strategies.


Asunto(s)
Antocianinas/efectos de la radiación , Carotenoides/efectos de la radiación , Clorofila/efectos de la radiación , Hojas de la Planta/efectos de la radiación , Antocianinas/metabolismo , Carotenoides/metabolismo , Clorofila/metabolismo , Luz , Fotosíntesis/efectos de los fármacos , Hojas de la Planta/metabolismo , Plantas/metabolismo , Plantas/efectos de la radiación
15.
Sci Rep ; 9(1): 14563, 2019 10 10.
Artículo en Inglés | MEDLINE | ID: mdl-31601927

RESUMEN

Research has shown that varying spatial scale through the selection of the total extent of investigation and the grain size of environmental predictor variables has effects on species distribution model (SDM) results and accuracy, but there has been minimal investigation into the interactive effects of extent and grain. To do this, we used a consistently sampled range-wide dataset of giant panda occurrence across southwest China and modeled their habitat and distribution at 4 extents and 7 grain sizes. We found that increasing grain size reduced model accuracy at the smallest extent, but that increasing extent negated this effect. Increasing extent also generally increased model accuracy, but the models built at the second-largest (mountain range) extent were more accurate than those built at the largest, geographic range-wide extent. When predicting habitat suitability in the smallest nested extents (50 km2), we found that the models built at the next-largest extent (500 km2) were more accurate than the smallest-extent models but that further increases in extent resulted in large decreases in accuracy. Overall, this study highlights the impacts of the selection of spatial scale when evaluating species' habitat and distributions, and we suggest more explicit investigations of scale effects in future modeling efforts.


Asunto(s)
Distribución Animal , Conservación de los Recursos Naturales , Ecosistema , Especies en Peligro de Extinción , Ursidae/fisiología , Animales , China , Ecología , Geografía , Modelos Teóricos , Reproducibilidad de los Resultados
16.
Environ Sci Pollut Res Int ; 26(18): 18651-18661, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31055756

RESUMEN

Protected areas (PAs) are considered a cornerstone of biodiversity conservation, and the number and extent of PAs are expanding rapidly worldwide. While designating more land as PAs is important, concerns about the degree to which existing PAs are effective in meeting conservation goals are growing. Unfortunately, conservation effectiveness of PAs and its underlying determinants are often unclear across large spatial scales. Using PAs in China as an example, we evaluated the effectiveness of 472 PAs established before 2000 in reducing deforestation between 2000 and 2015. Our results show that the majority (71%) of the PAs were effective in reducing deforestation. Without their establishment, deforestation within the PAs would have increased by about 50% (581 km2), with about 1271 megaton of carbon per year not being sequestered. We also found some attributes of PAs, including surrounding deforestation level, roughness of terrain, and travel time to the nearest city, are significantly related to their effectiveness in reducing deforestation. Our findings highlight the need of systematically evaluating the effectiveness of PAs and incorporating this effectiveness into conservation planning and management to more fully realize the goals of PAs not only in China but also around the world.


Asunto(s)
Conservación de los Recursos Naturales/métodos , Biodiversidad , Secuestro de Carbono , China , Agricultura Forestal , Humanos
17.
PLoS One ; 13(1): e0189496, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29320501

RESUMEN

Multiple factors introduce uncertainty into projections of species distributions under climate change. The uncertainty introduced by the choice of baseline climate information used to calibrate a species distribution model and to downscale global climate model (GCM) simulations to a finer spatial resolution is a particular concern for mountainous regions, as the spatial resolution of climate observing networks is often insufficient to detect the steep climatic gradients in these areas. Using the maximum entropy (MaxEnt) modeling framework together with occurrence data on 21 understory bamboo species distributed across the mountainous geographic range of the Giant Panda, we examined the differences in projected species distributions obtained from two contrasting sources of baseline climate information, one derived from spatial interpolation of coarse-scale station observations and the other derived from fine-spatial resolution satellite measurements. For each bamboo species, the MaxEnt model was calibrated separately for the two datasets and applied to 17 GCM simulations downscaled using the delta method. Greater differences in the projected spatial distributions of the bamboo species were observed for the models calibrated using the different baseline datasets than between the different downscaled GCM simulations for the same calibration. In terms of the projected future climatically-suitable area by species, quantification using a multi-factor analysis of variance suggested that the sum of the variance explained by the baseline climate dataset used for model calibration and the interaction between the baseline climate data and the GCM simulation via downscaling accounted for, on average, 40% of the total variation among the future projections. Our analyses illustrate that the combined use of gridded datasets developed from station observations and satellite measurements can help estimate the uncertainty introduced by the choice of baseline climate information to the projected changes in species distribution.


Asunto(s)
Biodiversidad , Ecosistema , Incertidumbre , Animales , Bambusa , Cambio Climático , Probabilidad
18.
Ecol Appl ; 17(4): 1019-30, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17555215

RESUMEN

Global biodiversity loss is largely driven by human activities such as the conversion of natural to human-dominated landscapes. A popular approach to mitigating land cover change is the designation of protected areas (e.g., nature reserves). Nature reserves are traditionally perceived as strongholds of biodiversity conservation. However, many reserves are affected by land cover changes not only within their boundaries, but also in their surrounding areas. This study analyzed the changes in habitat for the giant panda (Ailuropoda melanoleuca) inside Wolong Nature Reserve, Sichuan, China, and in a 3-km buffer area outside its boundaries, through a time series of classified satellite imagery and field observations. Habitat connectivity between the inside and the outside of the reserve diminished between 1965 and 2001 because panda habitat was steadily lost both inside and outside the reserve. However, habitat connectivity slightly increased between 1997 and 2001 due to the stabilization of some panda habitat inside and outside the reserve. This stabilization most likely occurred as a response to changes in socioeconomic activities (e.g., shifts from agricultural to nonagricultural economies). Recently implemented government policies could further mitigate the impacts of land cover change on panda habitat. The results suggest that Wolong Nature Reserve, and perhaps other nature reserves in other parts of the world, cannot be managed as an isolated entity because habitat connectivity declines with land cover changes outside the reserve even if the area inside the reserve is well protected. The findings and approaches presented in this paper may also have important implications for the management of other nature reserves across the world.


Asunto(s)
Conservación de los Recursos Naturales , Ecosistema , Ursidae , Animales , China
19.
Nat Ecol Evol ; 1(11): 1635-1638, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28963522

RESUMEN

The conservation status of the iconic giant panda is a barometer of global conservation efforts. The IUCN Red List has downgraded the panda's extinction risk from "endangered" to "vulnerable". Newly obtained, detailed GIS and remotely sensed data applied consistently over the last four decades show that panda habitat covered less area and was more fragmented in 2013 than in 1988 when the species was listed as endangered.


Asunto(s)
Conservación de los Recursos Naturales/métodos , Ecosistema , Especies en Peligro de Extinción , Tecnología de Sensores Remotos/métodos , Ursidae , Animales , China , Modelos Biológicos
20.
J Plant Physiol ; 201: 101-110, 2016 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-27374843

RESUMEN

One of the main factors affecting vegetation productivity is absorbed light, which is largely governed by chlorophyll. In this paper, we introduce the concept of chlorophyll efficiency, representing the amount of gross primary production per unit of canopy chlorophyll content (Chl) and incident PAR. We analyzed chlorophyll efficiency in two contrasting crops (soybean and maize). Given that they have different photosynthetic pathways (C3 vs. C4), leaf structures (dicot vs. monocot) and canopy architectures (a heliotrophic leaf angle distribution vs. a spherical leaf angle distribution), they cover a large spectrum of biophysical conditions. Our results show that chlorophyll efficiency in primary productivity is highly variable and responds to various physiological and phenological conditions, and water availability. Since Chl is accessible through non-destructive, remotely sensed techniques, the use of chlorophyll efficiency for modeling and monitoring plant optimization patterns is practical at different scales (e.g., leaf, canopy) and under widely-varying environmental conditions. Through this analysis, we directly related a functional characteristic, gross primary production with a structural characteristic, canopy chlorophyll content. Understanding the efficiency of the structural characteristic is of great interest as it allows explaining functional components of the plant system.


Asunto(s)
Clorofila/metabolismo , Productos Agrícolas/crecimiento & desarrollo , Productos Agrícolas/metabolismo , Productos Agrícolas/efectos de la radiación , Luz , Fotosíntesis/efectos de la radiación , Hojas de la Planta/metabolismo , Hojas de la Planta/efectos de la radiación , Glycine max/fisiología , Glycine max/efectos de la radiación , Factores de Tiempo , Agua/metabolismo , Zea mays/crecimiento & desarrollo , Zea mays/fisiología , Zea mays/efectos de la radiación
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